Geekend: Familiar Faces Can Be Friendly (Or Dangerous)
Studies show we pick our friends -- and employees -- based on visible and invisible similarities.
You can pick your friends. You can pick your nose. And you can pick your friend based on their noses. A study making headlines this week shows that a genetic test can help determine better than chance whether two people will become friends, because we pick friends with genetic similarities, from shape of noses to how those noses smell things.
We've known instinctively for a long time (and proved it with a study in 2011) that people pick friends who look like them. In the study, students in school, when given a choice, were shown to sit next to people of the same gender, race, and general appearance.
But it turns out that this selection goes way deeper than appearance. We also instinctively seek genetic similarities that are impossible to see with the naked eye, so every one of your friends isn't going to look just like you. As mentioned, one of the things we look for in a friend is a similar sense of smell, and we're still mapping others. The similarities account for only about 1% of our genes, but that's enough to be as closely related as fourth cousins.
We don't know exactly what or how many similarities we look for, because the data is incomplete. The research, conducted by professors at Yale and University of California San Diego, used a 1948 study that linked pairs of friends for lifestyle and genetic markers to help determine heart disease risk. The only downside of the 1948 study is that it was centered in Boston and focused on people of Italian-American descent. We're not sure how easily the results of that study apply to other ethnic groups.
Still, the researchers are pretty sure it transfers, because the authors see our propensity to pick genetically similar friends as an evolutionary strategy. Not only do we look for certain similarities, but we also look for differences in one key area: immune systems. That is, we look for friends who are immune to things we aren't immune to. It makes sense, because if your friend can't get a particular disease there's no way you're getting it from him.
How are we detecting these genetic similarities? Are we smelling them through body chemicals? Are we seeing clues we don't understand consciously?
No one knows, but I'm guessing we can see them in the way we pick our pets. Have you ever noticed how much certain people look like their pets?
There's a reason: We like to look at ourselves. Studies have shown that women with long hair prefer dogs with floppy ears. The ears remind them of their hair. The selection goes beyond appearance to personality type. We pick types of pets and breeds based on personality. We want pets (and friends) like us.
How do we even identify people who are "like" us in ways beyond appearance? The brain has mechanisms, called heuristics, that help see similarities. Have you ever wandered down a foreign city street for the first time and feel like you're seeing friends' faces everywhere? That's your brain trying to make the familiar out of the unfamiliar.
That's a similar (though different) mechanism. Our brain is trying to find something in our current experience that matches our previous experiences so we can better understand what we're seeing.
It's entirely possible we're picking up on genetic clues that help us know about other inner workings of the body. For instance, a study showed that there are roughly 14 types of noses in England. We often make assumptions about people and their character based on noses. It's possible that we're not only seeing character in those noses, but also instinctually seeing genetic similarities, including olfactory prowess and even more obscure genetic traits.
These types of heuristic judgments aren't bad by themselves. They help us make quick decisions that are often good shortcuts to the right answer. We
David has been writing on business and technology for over 10 years and was most recently Managing Editor at Enterpriseefficiency.com. Before that he was an Assistant Editor at MIT Sloan Management Review, where he covered a wide range of business topics including IT, ... View Full Bio
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